USB and MPC 40000

Two things. I'm getting a mid high hum whenever i plug my usb cable from the mpc 4000 to my Mac CPU. Anybody heard of this. The other thing is sometimes when my keyboard (typing, not music) is plugged to the mpc 4000 front port usb, it doesn't work. It will work (I'm able to name tracks and seq. etc) and then it will stop. (no response) ANY IDEAS. Please don't think it's the cable. I've done that already.



Thanks

Try another USB cable. The MPC is rather picky when it comes to USB cables.

When do you have a hum?
Wich soundcard do you use? If its a soundcard wich needs power, than thats your problem.


Be more specific.

i get the hum as soon as i connect the usb cable. I'm using pro tools mix plus system.

Hi,

It sounds like you have a ground problem. This most of the time occurs when there is a ground loop in your system. Make sure all your instruments have their power cords plugged into the same "fusegroup". If all devices are in the same group and you still have this problem, pick the device in the loop that is savest to unground and test if your problem is resolved. In my case I plugged my laptop in a groundless electric socket to solve the problem.

I had the problem with the keyboard as well. I'm not sure how and when the failure occurs yet though.

Best of luck, Cheers!

bleepfreak is correct

yo ... don't wanna panic .... but if you gotta ground problem you better sort it out NOW.

my stupid electrician simply didn't ground my basement which i don't use for too long time. in my basement there where to little plugs so i asked him to put some. however the entire building is grounded but just this room where most electricity is - he just put all the plugs and didn't ground it - btw: every electrician knows how to ground. however ... because of a wack amplifier which i even hardly ever use within weeks i been blowing away half of my setup ... no joke - it still hurts!

... not sure bout bleepfreaks advice to plug everything into the seme fusegroup - i had everything plugged like this - but imo if the place your at has an overall groundproblem - such as it was here - you better make sure to ground it properly and you ll never have any problem thisregarding anymore ...

might sound exagerated to you but my experience really was a nightmare ... if i were you i d check it asap ... go to an electrician and let those values be measured ... he is able to measure it in 5 mins ...

... don't understand much of electricity and grounds - but seen half of my setup gone - its nearly all repaired now but it was much, much more expensive than to put some proper ground in the first place ...

btw: really don't wanna panic ... but if i hear somethin related to groundproblem ... it always reminds me of that nightmare ... so i just wanna warn ...

some early signs that a place not grounded shows which i experienced here and which are now gone are ... ie your bulbs have a too short lifetime, pluging/unpluging cables ya get some sort of slight electroshock, vibrations, ... dunno the appropriate word in english ... once all your sounds sound slightly distorted or half of your monitors don't push out any sound anymore its fukkin late ...

really hope you or anybody else in here never ever will experience that sort of problem ... its been 3 month that i couldn't do any music at all coz half of my setup was in repair ... just started again a few weeks ago ...

... in my case next to the electrician the main bytch used to be my guitar amp i guess ... so i d be careful with all sort of amps til you find the cause of your problem ...

... hoping that it ain't this sort of problem i wish ya good luck ...

Before you start calling an electrician try seperating any power cords from the usb and all instrument cables and monitors, you could be getting Electromagnetic interfernce (EMI). Also is your USB cable shielded? having a shielded USB cable will help to reject EMI.

Sorry for not noticing this earlier. You stated that you have a problem typing in names using a keyboard as well. It truly sounds as if there is a problem with the usb port on the MPC. you should just go ahead and call a service center.

Would this also happen with midi cables in a midi setup?

I have 2 other sequencers sync'ed to my mpc4000 and now I hear static when I do real-time edit changes to patches on the other sequencers. At one point the sound just completely disappeared.

All of my cables are bunched up so if there is interference I probably have it between the power cables and the midi.

No badacid, it won't. There are opto-couplers on each side of a midi connection that interrupt the ground. The digital MIDI signal is converted into light and converted back into a digital signal again. This way it eliminates these kind of problems and your system is protected against unwanted high voltages due to faulty wiring etc.